Development tools for Zephyr on STM32Workbench for Zephyr: VS Code extension to set up, build, flash and debug Zephyr applications on STM32.Devicetree manager: browse, edit and visualize Zephyr devicetree, STM32CubeMX-like for Zephyr.
You should be able to reprogram option bytes to ReaD Protection level 0.
In STLink Utility, go to Target - Option Bytes window and change the RDP to level 0 and reprogram.